src/zisp/lib/list.zig


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const value = @import("../value.zig");

const Value = value.Value;

pub fn reverse(list: Value) Value {
    return reverseWithTail(list, value.nil);
}

pub fn reverseWithTail(list: Value, tail: Value) Value {
    var head = list;
    var result = tail;
    while (!value.nil.eq(head)) {
        const p = value.pair.unpack(head);
        result = value.pair.cons(p[0], result);
        head = p[1];
    }
    return result;
}